SmogRank / Countries / United States / Illinois

Most polluted cities in Illinois, United States

33 measured cities, last 7 days; 0 above the WHO 24-hour guideline. Worst: Wheaton at 10.8 µg/m³, #426 in the world.

28 good  5 moderate

  1. 1Wheatonlow-cost sensors 10.8
  2. 2Calumet City 9.9
  3. 3Bridgeview 9.8
  4. 4Brookfield 9.5
  5. 5Blue Islandlow-cost sensors 9.1
  6. 6Franklin Park 8.9
  7. 7Naperville 8.8
  8. 8Nileslow-cost sensors 8.8
  9. 9Oak Lawn 8.8
  10. 10Evergreen Parklow-cost sensors 8.7
  11. 11Skokielow-cost sensors 8.7
  12. 12Park Ridgelow-cost sensors 8.5
  13. 13Evanstonlow-cost sensors 7.8
  14. 14Chicago 7.7
  15. 15East Saint Louis 7.6
  16. 16Elgin 7.4
  17. 17Aurora 7.3
  18. 18Peoria 7.1
  19. 19Elmwood Park 7.0
  20. 20Granite City 6.9
  21. 21Dolton 6.9
  22. 22Rockford 6.8
  23. 23Decatur 6.6
  24. 24Upper Alton 6.6
  25. 25Moline 6.5
  26. 26Joliet 6.1
  27. 27Northbrook 6.1
  28. 28Cary 5.9
  29. 29Springfield 5.5
  30. 30Des Plaines 5.5
  31. 31Bloomington 5.4
  32. 32Champaign 5.4
  33. 33Zion 5.3
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+

Estimated: cities without a monitor

Illinois cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.

City7-day estimateBand
North Peoria≈ 6 µg/m³Good
Waukegan≈ 5 µg/m³Good
Cicero≈ 7 µg/m³Good
Arlington Heights≈ 9 µg/m³Good
Schaumburg≈ 8 µg/m³Good
Bolingbrook≈ 9 µg/m³Good
Palatine≈ 9 µg/m³Good
Orland Park≈ 9 µg/m³Good
Tinley Park≈ 8 µg/m³Good
Berwyn≈ 7 µg/m³Good
Mount Prospect≈ 9 µg/m³Good
Normal≈ 6 µg/m³Good
Oak Park≈ 7 µg/m³Good
Hoffman Estates≈ 8 µg/m³Good
Downers Grove≈ 9 µg/m³Moderate
Glenview≈ 7 µg/m³Good
Elmhurst≈ 9 µg/m³Moderate
Lombard≈ 9 µg/m³Moderate
DeKalb≈ 7 µg/m³Good
Plainfield≈ 8 µg/m³Good
Urbana≈ 6 µg/m³Good
Belleville≈ 6 µg/m³Good
Bartlett≈ 8 µg/m³Good
Buffalo Grove≈ 9 µg/m³Good
Quincy≈ 7 µg/m³Good
Streamwood≈ 8 µg/m³Good
Crystal Lake≈ 6 µg/m³Good
Carol Stream≈ 8 µg/m³Good
Romeoville≈ 9 µg/m³Good
Rock Island≈ 8 µg/m³Good
Carpentersville≈ 8 µg/m³Good
Hanover Park≈ 8 µg/m³Good
Wheeling≈ 9 µg/m³Good
Addison≈ 9 µg/m³Moderate
Glendale Heights≈ 8 µg/m³Good
Oswego≈ 8 µg/m³Good
Woodridge≈ 9 µg/m³Good
Elk Grove Village≈ 9 µg/m³Good
Pekin≈ 5 µg/m³Good
St. Charles≈ 8 µg/m³Good

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SmogRank, most polluted cities in Illinois, United States, PM2.5, last 7 days to 2 Oct 2026, 00:00 UTC, smogrank.com/us/region/illinois?w=7d.

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Updated 2026-10-02 00:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.